"It's a bit difficult, especially for some players," he said. "I think for some of the boys it is not a big problem to play match after match with two days' difference.

"For some others it is more difficult – their nature, their ages, their DNA. It is not so easy.

"We have important injuries and we do not have so many players to rotate. In some positions we have no choice. Of course, [Chelsea] are much better prepared for the game than us.

"We don’t train. We recover from matches. We try to give the players the best conditions to recover but, honestly, on the pitch there are no conditions to work.

"We analyse matches, we analyse opponents but to work on the pitch, with dynamism and intensity, at this moment is impossible."

A third defeat at the hands of Chelsea across all competitions this season would underline the gap between the two clubs, but Mourinho feels it is open to interpretation whether his first year in the Old Trafford dugout has been a success.

"It depends on the way you analyse it," he added. "You could say my record at home is not a good one, you could also say that my record away from home is very good.

"You can say that I won a trophy in the first season but you can forget it too soon – I don’t know what is a good season for you and for me.

"For me a good season is to be ready for every match and fight for every match for the best result and to defend Man United prestige.

"We are not fighting for the title, we are just fighting to finish top four. It is an important thing but the important thing for this club is to fight for titles and the only title we can win is the Europa League."